Incandescent lamp.



F. G. TILLEY.

v INCANDESCENT LAMP. APPLICATION FILED JAN. 31. 1911.

1,279,789. Patented Sept. 24,1918,

WITN asses [j wwmbmk.

ATTORNEY UNITED STATES PATENT OFFICE.

FREDERICK v'JI'IIILLEY, OF ST. LOUIS, MISSOURI, ASSIGNOR F ONE-FOURTH TOCHAS. E. ROTT,,0F SAPPINQTON, MISSOURI.

INCANDESCENT LAMP.

Specification of Letters Patent- Patented. Sept. 24, 1918.

' Application filed January 31, 1917. Serial No. 145,716.

To all whom it may concern:

Be it known that I, FREDERICK G; TILLEY, a citizenv of the UnitedStates, residing at St. Louis, in the State of Missouri, have inventedcertain new and useful Improvements in Incandescent Lamps, of which thefollow- 7 ing is a specification.

This invention relates to incandescent lamps. I

One of the main ob ects of the mventlon is to provide a lamp having anincandescing or glow member or filament of coiled shape so as to providea large light radiating surthe danger of breakage due to vibration andsudden jars to a minimum. A still further object is to provide apermanently magnetized element of coiled shape the turns of which arearranged alternately with, and mid-way between, the convolutions of thefilament so as to oppose movement of the filament. turns in eitherdirection axially of the filament coil. Further objects will appear fromthe detail description.

The single figure of the drawings is a central section taken through thelamp constructed in accordance with my invention.

The lamp is rovided with the customary glass bulb or g obe 1 from whichthe air is removed by a mercury pump or the like to form a vacuum, orthe globe may be filled with nitrogen, argon, or other similar gas whichis inert with respect to the filament. v

This globe is provided with a radially extending standard2 the. innerportion of which is reduced to form an integral inwardly extendingsupporting post 3 the inner end of which is enlarged to form an integraldisk 4. A lead 5 is mounted through the standard 2 and connected, to oneterminal 6 of a socket 7, which is secured about the base of standard 2.A lead 8 is mounted through standard 2 in spaced relation to lead 5 andis connected to the usual metallic covering 9 of socket 7, this socketbeing adapted to be threaded into a wall socket 10 of standardconstruction in the usual manner.

The lead 5 is extended upward through .post 3 at the center thereof Theupper end of this lead is electrically connected to the upper end of acoiled glow member or filament 11, as at 11*. This filament is coiledabout the post 3 concentric therewith and its lower end is electricallyconnected to'the inner end of lead 8 as at 11". By this means arelatively long filament having a comparatively large light radiatingsurface may be mounted within the bulb 1 and has its ends connected tothe leads 5 and 8 in the usual manner. This filament is made fromtungsten or other suitable infusible material. A magnetized coiledmember 12 is mounted about the post 3 with its upper end secured to disk4 as at 12 and its lower end secured to the standard 2 as at 12*. Thecoil of this member is of the same diameter as the coil-of filament 11,and the convolutions of member 12 are disposed alternately with, andmidway between, the convolutions of filament 11. This member 12 may beformed from highly tempered steel and is magnetized, to provide aglass-hard permanent magnet. The magnetic stresses between theconvolutions of the member 12 serve to maintain the convolutions of thefilamept midway betweenthe turns of the member 12, movement of theconvolutions of the filament in either direction axially of the filamentcoil being opposed by the magnetic-traction of the convolutions of themagnetized member. If desired, the magnetic member 12 may be made ofmagnetite so as to provide a permanent magnet instead of forming thismember from highly tempered steel which is magnetized. A

By providing a coiled filament in combination with a magnetized coiledmember the convolutions of which are disposed alterused, or is inoperation. When the current is turned on it flows through the filamentso as to cause incandescence thereof. This current will, necessarily,flow through the magnetic fields between the coils of member 12 and themagnetic stresses Will urge the coils of the filament in oppositedirections thus maintaining the convolutions of the same in centralposition between the convolutions of the magnetic coil. In this manner,when the light is in use, the filament will be held in proper operativeposition and sustained by the magnetic stresses of the member 12 so asto eliminate breakage or fracturing of the filament through sudden joltsor jars. As the magnetic coil is formed from very highly tempered steelas to provide a glass-hard permanent magnet, it Will not be readilydemagnetized by the heat of thfe filament, but Will have a relativelylong li e.

In addition to serving by magnetic attraction to oppose movement of theconvolutions of the filament coil in either direction axially of thesame, the member 12 also acts as a guard to prevent excessive movementof any of the convolutions of the filament, the coils of this member 12being so positioned as to engage the convolutions of the filament thuspositively limiting movement of the same in the event of the lamp beingsubjected to any unusual jar such as would tend to cause excessivemovement of the filament coils. By this means the magnetized member 12acts to oppose movement of the filament under ordinary conditions, andto positively prevent excessive movement of the filament in between theconvolutions of said coiled member.

2. In electric lamps a coiled magnetized member, and a similarly coiledfilament, the convolutions of the filament being disposed midway betweenthe convolutions of the said magnetized member.

3. In electric lamps, a coiled filament of magnetic material, andacoiled magnetized member having its convolutions disposed al ternatelywith and midway between the convolutions of said filament.

4c. In electric lamps, a coiled filament of magnetic material, and apermanently magnetized coiled member disposed with its convolutionsmidway between the convolutions of the said filament.

In testimony whereof I aifiX my signature in presence of two Witnesses.

FREDERICK G. TILLEY.

Witnesses:

GHAs. F. Ro'rr, DELLA P. Proms.

